I just purchesed a 1991 S10 and was wondering where the Oxygen sensor is at. I was told it was on the exhaust manifold and cannot find it anywhere. Please help?

 

I have a 93 s-10 with a 2.8 v6 and mine is located on the exhust pipe on the left side before the catalytic converter. Mine has a single wire connector. I'd suggest to buy or rent the special socket to take it out. It will make it alot easier. Hope this helps.